The invention is a process and a device for packaging a liquid, semi-liquid, soft or fine-powder product in a closed foil tube in accordance with the introduction to Patent claim 1.
A process mentioned earlier has for example been published in DE 38 41 056 and 38 41 945 whose object is that in particular a meltable cheese mass is poured into a fully closed foil tube, and that corresponding form webs arranged on a conveyer form successive sections out of the foil tube closed with the cheese mass. In the area of these separating webs the meltable cheese mass is expelled from the foil tube, and the foil tube is then sealed and cooled off in this area. After cooling, the individual slices still coherent in the tube are then cut and taken to a stacking device.
In the above-named process the separation of the individual sections in the foil tube takes place in a hot state. This has the disadvantage that the foil changes in its linear expansion due to the heat impact from the hot mass thus resulting in changes in length in the foil in the area between filling the hot mass and the subsequent sealing station. This requires a relatively wide sealing seam in order to obtain sealing of the individual foil sections, i.e. to guarantee a sufficiently accurate sealing quality. Indeed, in order to accommodate the various changes in foil length, the sealing seam must be wide in order to guarantee sealing in the separated web area of the foil even under extreme changes in length.
However, when using relatively wide sealing seams of for example 16 mm it is not easy to realize a complete and clean expulsion of the hot mass from the sealing area thus affecting sealing quality. The risk was that the sealing seam would be soiled by product residue and that it would not be closed properly. In other words, no gas-tight seal could be guaranteed and the foodstuff contained in the foil tube would spoil more readily.
In addition, the application of relatively wide sealing seams had the disadvantage of a relatively high foil consumption, which translates into additional expenses of up to DM 50,000.00 per year with traditional production equipment and a normal production capacity. In addition, the foil used in the process was significantly more costly because sealing of this type required the use of a heat-resistant foil capable of withstanding the relatively high temperatures of the hot foodstuff of 80.degree.-90.degree. C. for example without showing any excessive non-permissible deformation.
In addition, the use of wide sealing seams shows that a so-called "foil tail" appears on the front ends of the individually cut packages and that it may turn out longer or shorter, thus affecting the subsequent stacking of individual packages.